Impala SQL Language Reference

Impala uses SQL as its query language. To protect user investment in skills development and query
design, Impala provides a high degree of compatibility with the Hive Query Language (HiveQL):

Because Impala uses the same metadata store as Hive to record information about table structure and
properties, Impala can access tables defined through the native Impala CREATE TABLE
command, or tables created using the Hive data definition language (DDL).

Impala supports data manipulation (DML) statements similar to the DML component of HiveQL.

Impala provides many built-in functions with the same
names and parameter types as their HiveQL equivalents.

Impala supports most of the same statements and
clauses as HiveQL, including, but not limited to JOIN, AGGREGATE,
DISTINCT, UNION ALL, ORDER BY, LIMIT and
(uncorrelated) subquery in the FROM clause. Impala also supports INSERT
INTO and INSERT OVERWRITE.